If Mary Chose Mr Ryder
Surprised how much I enjoyed the show. Nice antidote to the doom and gloom suffusing a lot of TV these days. (Sometimes I don't want to see current state of the world reflected back but I want happy escapism.)
It occurred to me if Mary chose Mr Ryder, she would be the wealthiest of the Bennet sisters. Mr Ryder is Lady Catherine de Bourgh's heir. Assuming he doesn't blow it, the de Bourgh fortune eclipses the fortune of Mr Darcy, more or less to be the wealthiest of the Bennet son-in-laws.
During this time, status equals wealth. A Duke is generally wealthier than a earl. A viscount is wealthier than a baron. A titled person is generally wealthier than an untitled person. Sir Lewis de Bourgh (Lady Catherine's husband) is titled; neither Mr Darcy nor his father are titled. Now, to be titled a sir, one has to do something extraordinary (Sir Isaac Newton) or be very rich (Sir Alan Sugar) or have aristocratic level wealth but from low born roots (baronetcies were created, i.e. bought, as a money making scheme for the monarch). Either way, nothing in P&P lead one to conclude the de Bourgh's did anything extraordinary else Mr Collins would not shut up about it; however, Mr Collins does repeatedly remark on their wealth.
So the de Bourgh would have a fortune that eclipses that of a rando gentleman. Now this fortune would have to massive to convince Fitzwilliam Darcy to have an understanding with Lady Catherine's daughter. If the de Bourghs fortune was small, why bother? That Fitzwilliam Darcy would give up said fortune for Elizabeth Bennet, and only for Elizabeth Bennet, can be seen as swapping something of value for another - Elizabeth Bennet is the heroine of P&P, she is, in Austen's estimation, to be the most important person in the novel-- someone so important and valuable that would equal what would cost Darcy to drop Anne and the inheritance.
It's just a fun thought. Mary may not have love Ryder but she wouldn't be unhappy. And in Austen's novels, not being unhappy is not insignificant and often the best available option for our often luckless protagonists.